Can a Mains socket be vertically inline with light switch

[JohnW2]

If both switch and socket were in-line with each other, then you still have potential vertical wall area of 7.5mm-15mm where the cable could possibly run vertically outside the permitted zones, even if the cable did enter the switch backbox! It may be within the zone as it enters the switch backbox but it could prior to entry and after exit, stray outside that zone. So not impossible!

Quite. I can't really ague since, as I said, very little is totally impossible. However, some things are incredibly improbable, and, IMO, life is too short to devote much time to contemplating them!

Kind Regards, John